Punching & Stamping

Characteristics of Punching & Stamping:

Process Overview:

• Punching is a process in which a tool, called a punch, is used to create holes or shapes in a sheet of metal by shearing it. The punch presses the material into a die, cutting out the desired shape. This process is commonly used to produce holes, slots, or other intricate shapes in metal sheets.
• Stamping involves the use of a die to form or shape a metal sheet. The process can include various operations such as bending, embossing, flanging, or coining, all performed in a single stroke of the press. Stamping is widely used to create complex shapes and designs in metal parts.

Types of Punching:

• Blanking:This is the process of cutting out a piece from a larger sheet of metal, typically to create a flat, usable part known as a blank. Blanking is often the first step in the production of parts that will undergo further processing.


• Piercing: Piercing is similar to blanking but focuses on creating holes or cutouts in the metal sheet. The material punched out is usually considered scrap, leaving the surrounding material as the final product.


• Notching: Notching involves cutting out shapes or angles from the edges of a metal sheet. It is often used in the preparation of metal sheets for further forming or assembly processes.

Types of Stamping:

• Progressive Stamping: In this process, a metal strip is fed through a series of stations, each performing a different operation such as cutting, bending, or punching. By the time the strip reaches the end of the line, the finished part is complete. Progressive stamping is ideal for high-volume production.


• Deep Drawing:Deep drawing is a stamping process where a flat sheet of metal is transformed into a hollow shape, such as a can or a cup, by drawing the metal into a die. This process is used to produce parts with significant depth relative to their diameter.


• Transfer Stamping: Similar to progressive stamping, but the part is transferred from one station to another by mechanical fingers rather than the strip moving through the dies. This allows for greater flexibility in the types of operations performed.

Material Considerations:

• Material Selection: The choice of material is critical for both punching and stamping. Common materials include steel, aluminum, brass, copper, and stainless steel. The material's ductility, thickness, and strength influence the choice of punching or stamping methods.


• Sheet Thickness: The thickness of the metal sheet affects the force required for punching or stamping. Thicker sheets require more robust equipment and tooling to achieve clean cuts and precise shapes.